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Degenerate conic

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4472:, there is a unique conic passing through them. If three of these points lie on a line, then the conic is reducible, and may or may not be unique. If no four points are collinear, then five points define a unique conic (degenerate if three points are collinear, but the other two points determine the unique other line). If four points are collinear, however, then there is not a unique conic passing through them – one line passing through the four points, and the remaining line passes through the other point, but the angle is undefined, leaving 1 parameter free. If all five points are collinear, then the remaining line is free, which leaves 2 parameters free. 81: 132: 25: 175: 3068: 1462: 338: 1633: 4475:
Given four points in general linear position (no three collinear; in particular, no two coincident), there are exactly three pairs of lines (degenerate conics) passing through them, which will in general be intersecting, unless the points form a
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Another type of degeneration occurs for an ellipse when the sum of the distances to the foci is mandated to equal the interfocal distance; thus it has semi-minor axis equal to zero and has eccentricity equal to one. The result is a
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Over the complex projective plane there are only two types of degenerate conics – two different lines, which necessarily intersect in one point, or one double line. Any degenerate conic may be transformed by a
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Pencils of circles: in the pencil of red circles, the only degenerate conic is the horizontal axis; the pencil of blue circles has three degenerate conics, the vertical axis and two circles of radius zero.
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Given three points, if they are non-collinear, there are three pairs of parallel lines passing through them – choose two to define one line, and the third for the parallel line to pass through, by the
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In the real plane, a degenerate conic can be two lines that may or may not be parallel, a single line (either two coinciding lines or the union of a line and the
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goes to 0; but, because they have conjugate complex points at infinity which become a double point on degeneration, cannot degenerate to two intersecting lines.
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by considering the pencil of conics through the four roots of the quartic, and identifying the three degenerate conics with the three roots of the
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Degenerate conics can degenerate further to more special degenerate conics, as indicated by the dimensions of the spaces and points at infinity.
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corresponding the parallel vertical lines and horizontal lines, and results in the degenerate conics falling at the standard points of
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The conic is degenerate if and only if the determinant of this matrix equals zero. In this case, we have the following possibilities:
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In the complex projective plane, all conics are equivalent, and can degenerate to either two different lines or one double line.
2994:, four points leave one parameter free), of which three are degenerate, each consisting of a pair of lines, corresponding to the 1268: 1062: 4865: 3071: 1361: 1149: 4745: 2073: 4808: 2022:. This determinant is positive, zero, or negative as the conic is, respectively, an ellipse, a parabola, or a hyperbola. 321:
form a pencil, which contains one or three degenerate conics. For any degenerate conic in the real plane, one may choose
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Faucette, William Mark (January 1996), "A Geometric Interpretation of the Solution of the General Quartic Polynomial",
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of the cone or when the cone degenerates to a cylinder and the plane is parallel to the axis of the cylinder. See
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Conics, also known as conic sections to emphasize their three-dimensional geometry, arise as the intersection of a
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goes to 0; but, because parabolae have a double point at infinity, cannot degenerate to two intersecting lines.
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Analogously, a conic can be classified as non-degenerate or degenerate according to the discriminant of the
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of conics. That is, if two real non-degenerated conics are defined by quadratic polynomial equations
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Two intersecting lines can degenerate to two parallel lines, by rotating until parallel, as in
1262: 736: 286: 88: 4617: 3530: 2691: 2564: 2317: 2268:{\displaystyle Q={\begin{bmatrix}A&B&D\\B&C&E\\D&E&F\\\end{bmatrix}}.} 1055:
Over the real affine plane the situation is more complicated. A degenerate real conic may be:
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Non-degenerate real conics can be classified as ellipses, parabolas, or hyperbolas by the
8: 3813: 2703: 1720: 1625: 1016: 990: 289:), or the null set (twice the line at infinity or two parallel complex conjugate lines). 252: 248: 4854: 4841: 4812: 4786: 4578: 4488: 3644: 2653: 2625: 2605: 2282:
Two intersecting lines (a hyperbola degenerated to its two asymptotes) if and only if
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Two parallel lines can degenerate to a double line by moving into each other, as in
4469: 4444: 2679: 282: 271: 3791:), this is a Type I linear system of conics, and is animated in the linked video. 4443:(degenerate because the ellipse is not differentiable at the endpoints) with its 3803: 2687: 275: 2642:
are not both zero. This case always occurs as a degenerate conic in a pencil of
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The case of coincident lines occurs if and only if the rank of the 3×3 matrix
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is an example of a degenerate conic consisting of twice the line at infinity.
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Hyperbolas can degenerate to two intersecting lines (the asymptotes), as in
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Note that this parametrization has a symmetry, where inverting the sign of
1442: 278:, a conic is degenerate if the plane goes through the vertex of the cones. 2706:
generally, arise as limits of non-degenerate conics, and are important in
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yielding the following pencil; in all cases the center is at the origin:
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so that the given degenerate conic belongs to the pencil they determine.
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Given two distinct points, there is a unique double line through them.
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or to a double line by rotating into each other about a point, as in
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Using the alternative definition of the conic as the intersection in
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ways of choosing 2 pairs of points from 4 points (counting via the
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Two parallel straight lines (a degenerate parabola) if and only if
1980:{\displaystyle M={\begin{bmatrix}A&B\\B&C\\\end{bmatrix}},} 232: 2673: 1632: 174: 131: 80: 24: 2990:(no three on a line), there is a pencil of conics through them ( 2643: 2183:
the discriminant of this form is the determinant of the matrix
255:. This means that the defining equation is factorable over the 1358:
Two parallel complex conjugate lines (no real point), such as
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into two lines, the line at infinity and the line of equation
4448: 2913:– throughout, one axis has length 2 and the other has length 240: 2683: 1449:
For any two degenerate conics of the same class, there are
1349:{\displaystyle x^{2}+y^{2}=0\Leftrightarrow (x+iy)(x-iy)=0} 4832:
Milne, J. J. (January 1926), "Note on Degenerate Conics",
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the pencil of conics through them can be parameterized as
1137:{\displaystyle x^{2}-y^{2}=0\Leftrightarrow (x+y)(x-y)=0} 2561:
A single line (and the line at infinity) if and only if
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Lasley, Jr., J. W. (May 1957), "On Degenerate Conics",
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goes to 0, but cannot degenerate to non-parallel lines.
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Such families arise naturally – given four points in
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A single point (a degenerate ellipse) if and only if
2471: 2410: 2349: 2320: 2288: 2192: 2076: 2035: 1996: 1931: 1837: 1749: 1723: 1642: 1559: 1471: 1429:{\displaystyle x^{2}+1=0\Leftrightarrow (x+i)(x-i)=0} 1364: 1271: 1232: 1217:{\displaystyle x^{2}-1=0\Leftrightarrow (x+1)(x-1)=0} 1152: 1065: 1019: 993: 923: 882: 844: 780: 745: 684: 644: 598: 557: 496: 450: 397: 351: 185: 142: 91: 35: 2173:{\displaystyle Ax^{2}+2Bxy+Cy^{2}+2Dxz+2Eyz+Fz^{2};} 4435:
A double line cannot degenerate to the other types.
2670:is 1; in all other degenerate cases its rank is 2. 638:, which has only one real point, is degenerate, as 4853: 4677: 4642: 4606: 4569: 4420: 4367: 4315: 4245: 4173: 4104: 4059: 4004: 3938: 3879: 3759: 3725: 3679: 3653: 3629: 3582: 3551: 3518: 3471: 3437: 3397: 3373: 3342: 3306: 3259: 3228: 3196: 3117: 3043: 2976: 2950: 2905: 2879: 2850: 2821: 2792: 2766: 2662: 2634: 2614: 2594: 2550: 2518: 2457: 2396: 2335: 2303: 2267: 2172: 2059: 2014: 1979: 1914: 1815: 1735: 1710: 1616: 1545: 1428: 1348: 1251: 1216: 1136: 1052:into any other degenerate conic of the same type. 1031: 1005: 979: 906: 868: 830: 763: 723: 670: 630: 581: 543: 474: 436: 383: 217: 161: 116: 67: 1441:Twice the line at infinity (no real point in the 4906: 4019:Parabolas can degenerate to two parallel lines: 3044:{\displaystyle \textstyle {{\binom {4}{2,2}}=3}} 2686:. Degeneracy occurs when the plane contains the 2536: 2321: 2289: 391:is degenerate as its equation can be written as 4119:Ellipses can degenerate to two parallel lines: 3794:A striking application of such a family is in ( 2674:Relation to intersection of a plane and a cone 4897:CRC Standard Mathematical Tables and Formulas 4827:, New York: The Macmillan Co., pp. x+405 3027: 3006: 1711:{\displaystyle 9x^{2}+12xy+4y^{2}-54x-36y+72} 1915:{\displaystyle Ax^{2}+2Bxy+Cy^{2}+2Dx+2Ey+F} 1546:{\displaystyle 3x^{2}-2xy-y^{2}-6x+10y-9=0,} 592:Similarly, the conic section with equation 263:) as the product of two linear polynomials. 4851: 4796: 4731: 4705: 1453:mapping the first conic to the second one. 4840:(180), The Mathematical Association: 7–9, 4780: 4246:{\displaystyle x^{2}+a^{2}y^{2}-a^{2}=0,} 3816:, when a conic degenerates to two lines. 2067:. Here the affine form is homogenized to 1922:, which is the determinant of the matrix 1226:A double line (multiplicity 2), such as 739:that intersect in the unique real point, 292:All these degenerate conics may occur in 16:2nd-degree plane curve which is reducible 4764: 3800:geometric solution to a quartic equation 3795: 3197:{\displaystyle (1+a)x^{2}+(1-a)y^{2}=2,} 2465:, and non-existent in the real plane if 1631: 1460: 336: 4005:{\displaystyle x^{2}-a^{2}y^{2}=a^{2},} 2343:. These lines are distinct and real if 4907: 4510:A simpler parametrization is given by 3445:ellipses with a horizontal major axis; 2702:Degenerate conics, as with degenerate 1823:is the union of the red and blue loci. 1816:{\displaystyle (3x+2y-6)(3x+2y-12)=0,} 1438:A single line and the line at infinity 4873: 4831: 4718: 2519:{\displaystyle D^{2}+E^{2}<(A+C)F} 2397:{\displaystyle D^{2}+E^{2}>(A+C)F} 980:{\displaystyle a(x^{2}+y^{2}-1)-bx=0} 4893:"7.2 The General Quadratic Equation" 4822: 4570:{\displaystyle ax^{2}+(1-a)y^{2}=1,} 4174:{\displaystyle x^{2}+a^{2}y^{2}-1=0} 3788: 3350:ellipses with a vertical major axis; 2404:(see second diagram), coincident if 1990:the matrix of the quadratic form in 774:The pencil of ellipses of equations 4809:Mathematical Association of America 4743: 4459: 3939:{\displaystyle x^{2}-a^{2}y^{2}=1,} 3084:For example, given the four points 3075: 917:The pencil of circles of equations 876:, into two parallel lines and, for 831:{\displaystyle ax^{2}+b(y^{2}-1)=0} 544:{\displaystyle a(x^{2}-y^{2})-b=0.} 251:of degree two) that fails to be an 13: 4669: 3880:{\displaystyle x^{2}-y^{2}=a^{2},} 3674: 3574: 3236:hyperbolae opening left and right; 3010: 2458:{\displaystyle D^{2}+E^{2}=(A+C)F} 1617:{\displaystyle (x-y+1)(3x+y-9)=0,} 14: 4926: 4825:Projective and related geometries 4800:The American Mathematical Monthly 4768:The American Mathematical Monthly 4316:{\displaystyle x^{2}-ay^{2}-1=0,} 2829:concretely, it is an ellipse for 1042: 735:. The conic consists thus of two 3066: 1059:Two intersecting lines, such as 345:The conic section with equation 285:), a single point (in fact, two 173: 130: 79: 23: 4368:{\displaystyle x^{2}-ay^{2}=0,} 3819: 3559:hyperbolae opening up and down, 2697: 1456: 1265:(only one real point), such as 4852:Pettofrezzo, Anthony (1978) , 4724: 4711: 4698: 4545: 4533: 4504: 3671: 3479:the parallel horizontal lines 3172: 3160: 3144: 3132: 3118:{\displaystyle (\pm 1,\pm 1),} 3109: 3091: 2939: 2931: 2767:{\displaystyle x^{2}+ay^{2}=1} 2692:Conic section#Degenerate cases 2510: 2498: 2449: 2437: 2388: 2376: 2054: 2036: 2009: 1997: 1801: 1777: 1774: 1750: 1602: 1581: 1578: 1560: 1417: 1405: 1402: 1390: 1387: 1337: 1322: 1319: 1304: 1301: 1205: 1193: 1190: 1178: 1175: 1125: 1113: 1110: 1098: 1095: 959: 927: 819: 800: 758: 746: 718: 703: 700: 685: 526: 500: 425: 413: 410: 398: 1: 4691: 4421:{\displaystyle x^{2}-a^{2}=0} 3726:{\displaystyle x^{2}-y^{2}=0} 3438:{\displaystyle -1<a<0:} 2992:five points determine a conic 2951:{\textstyle 1/{\sqrt {|a|}},} 631:{\displaystyle x^{2}+y^{2}=0} 384:{\displaystyle x^{2}-y^{2}=0} 218:{\displaystyle x^{2}+y^{2}=0} 68:{\displaystyle x^{2}-y^{2}=0} 4856:Matrices and Transformations 4678:{\displaystyle 0,1,\infty .} 4480:(one pair is parallel) or a 4060:{\displaystyle x^{2}-ay-1=0} 3680:{\displaystyle a\to \infty } 3343:{\displaystyle 0<a<1:} 3267:the parallel vertical lines 1831:of the non-homogeneous form 1146:Two parallel lines, such as 724:{\displaystyle (x+iy)(x-iy)} 437:{\displaystyle (x-y)(x+y)=0} 7: 4105:{\displaystyle x^{2}-ay=0,} 3630:{\displaystyle y=x,\ y=-x;} 3519:{\displaystyle y=-1,\ y=1;} 3398:{\displaystyle {\sqrt {2}}} 3307:{\displaystyle x=-1,\ x=1;} 2551:{\displaystyle \det M>0} 2304:{\displaystyle \det M<0} 671:{\displaystyle x^{2}+y^{2}} 332: 259:(or more generally over an 10: 4931: 4484:(two pairs are parallel). 4453:radial elliptic trajectory 3887:or to two parallel lines: 3827:In the real affine plane: 3738:This then loops around to 3583:{\displaystyle a=\infty :} 310:, the conics of equations 261:algebraically closed field 4447:at the endpoints. As an 3787:. In the terminology of ( 3065: 3060: 2721:of curves (1-dimensional 1628:of the red and blue loci. 1465:The degenerate hyperbola 1050:projective transformation 117:{\displaystyle x^{2}-1=0} 4834:The Mathematical Gazette 4747:Linear Systems of Conics 4643:{\displaystyle y^{2}=1,} 4497: 3810:Pappus's hexagon theorem 3661:and taking the limit as 3552:{\displaystyle a<-1:} 2595:{\displaystyle A=B=C=0,} 2336:{\displaystyle \det M=0} 1636:The degenerate parabola 4607:{\displaystyle x^{2}=1} 4468:: given five points in 3812:is the special case of 3760:{\displaystyle a>1,} 3229:{\displaystyle a>1:} 3053:multinomial coefficient 2988:general linear position 2858:two parallel lines for 2851:{\displaystyle a>0,} 2793:{\displaystyle a\neq 0} 2723:linear system of conics 2712:moduli spaces of curves 2060:{\displaystyle (x,y,z)} 1263:complex conjugate lines 1252:{\displaystyle x^{2}=0} 907:{\displaystyle a=1,b=0} 869:{\displaystyle a=0,b=1} 737:complex conjugate lines 582:{\displaystyle a=0,b=1} 475:{\displaystyle a=1,b=0} 287:complex conjugate lines 268:three-dimensional space 162:{\displaystyle x^{2}=0} 4874:Spain, Barry (2007) , 4679: 4644: 4608: 4571: 4466:defined by five points 4422: 4369: 4317: 4247: 4175: 4106: 4061: 4006: 3946:or to the double line 3940: 3881: 3761: 3727: 3681: 3655: 3631: 3584: 3553: 3520: 3473: 3439: 3399: 3381:a circle (with radius 3375: 3344: 3308: 3261: 3230: 3198: 3119: 3045: 2978: 2958:which is infinity for 2952: 2907: 2906:{\displaystyle a<0} 2881: 2852: 2823: 2800:but is degenerate for 2794: 2774:is non-degenerate for 2768: 2664: 2636: 2616: 2596: 2552: 2520: 2459: 2398: 2337: 2305: 2269: 2174: 2061: 2016: 1981: 1916: 1824: 1817: 1737: 1712: 1629: 1618: 1547: 1451:affine transformations 1430: 1350: 1253: 1218: 1138: 1033: 1007: 981: 914:, into a double line. 908: 870: 832: 765: 725: 672: 632: 583: 545: 476: 438: 385: 342: 219: 163: 118: 69: 4680: 4645: 4609: 4572: 4423: 4370: 4318: 4248: 4176: 4107: 4062: 4007: 3941: 3882: 3762: 3728: 3682: 3656: 3632: 3585: 3554: 3521: 3474: 3472:{\displaystyle a=-1:} 3440: 3400: 3376: 3345: 3309: 3262: 3231: 3199: 3120: 3046: 2979: 2953: 2908: 2887:and a hyperbola with 2882: 2853: 2824: 2795: 2769: 2665: 2637: 2617: 2597: 2553: 2521: 2460: 2399: 2338: 2306: 2270: 2175: 2062: 2017: 2015:{\displaystyle (x,y)} 1982: 1917: 1818: 1738: 1713: 1635: 1619: 1548: 1464: 1431: 1351: 1254: 1219: 1139: 1034: 1008: 982: 909: 871: 833: 766: 764:{\displaystyle (0,0)} 726: 673: 633: 584: 546: 477: 439: 386: 340: 220: 164: 119: 70: 4823:Levy, Harry (1964), 4654: 4618: 4585: 4514: 4386: 4327: 4269: 4185: 4123: 4071: 4023: 3950: 3891: 3835: 3767:since pencils are a 3742: 3691: 3665: 3645: 3594: 3565: 3531: 3483: 3451: 3411: 3385: 3374:{\displaystyle a=0:} 3356: 3319: 3271: 3260:{\displaystyle a=1:} 3242: 3211: 3129: 3088: 2998: 2977:{\displaystyle a=0.} 2962: 2917: 2891: 2880:{\displaystyle a=0,} 2862: 2833: 2822:{\displaystyle a=0;} 2804: 2778: 2729: 2654: 2626: 2606: 2565: 2533: 2469: 2408: 2347: 2318: 2311:(see first diagram). 2286: 2190: 2074: 2033: 1994: 1929: 1835: 1747: 1721: 1640: 1557: 1469: 1362: 1269: 1230: 1150: 1063: 1017: 991: 921: 880: 842: 778: 743: 682: 642: 596: 555: 494: 448: 395: 349: 183: 140: 89: 33: 4579:affine combinations 4464:A general conic is 4181:or the double line 4067:or the double line 3590:the diagonal lines 2704:algebraic varieties 1736:{\displaystyle =0,} 1032:{\displaystyle x=0} 1006:{\displaystyle a=0} 249:polynomial equation 4675: 4640: 4604: 4567: 4489:parallel postulate 4418: 4365: 4313: 4243: 4171: 4102: 4057: 4002: 3936: 3877: 3757: 3723: 3677: 3651: 3627: 3580: 3549: 3516: 3469: 3435: 3395: 3371: 3340: 3304: 3257: 3226: 3194: 3115: 3041: 3040: 2974: 2948: 2903: 2877: 2848: 2819: 2790: 2764: 2660: 2632: 2612: 2592: 2548: 2516: 2455: 2394: 2333: 2301: 2265: 2256: 2170: 2057: 2029:quadratic form in 2012: 1977: 1968: 1912: 1825: 1813: 1733: 1708: 1630: 1614: 1543: 1426: 1346: 1249: 1214: 1134: 1029: 1003: 977: 904: 866: 828: 761: 721: 668: 628: 579: 551:The limiting case 541: 472: 434: 381: 343: 215: 159: 114: 65: 4876:Analytical Conics 4867:978-0-486-63634-4 4581:of the equations 3654:{\displaystyle a} 3611: 3503: 3393: 3291: 3082: 3081: 3025: 2943: 2717:For example, the 2663:{\displaystyle Q} 2635:{\displaystyle E} 2615:{\displaystyle D} 1743:which factors as 1553:which factors as 1261:Two intersecting 838:degenerates, for 678:is factorable as 253:irreducible curve 243:(a second-degree 4922: 4900: 4888: 4870: 4859: 4848: 4828: 4819: 4793: 4784: 4761: 4760: 4759: 4750:, archived from 4735: 4732:Pettofrezzo 1978 4728: 4722: 4715: 4709: 4706:Lasley, Jr. 1957 4702: 4685: 4684: 4682: 4681: 4676: 4649: 4647: 4646: 4641: 4630: 4629: 4613: 4611: 4610: 4605: 4597: 4596: 4576: 4574: 4573: 4568: 4557: 4556: 4529: 4528: 4508: 4470:general position 4460:Points to define 4427: 4425: 4424: 4419: 4411: 4410: 4398: 4397: 4375:in each case as 4374: 4372: 4371: 4366: 4355: 4354: 4339: 4338: 4322: 4320: 4319: 4314: 4297: 4296: 4281: 4280: 4252: 4250: 4249: 4244: 4233: 4232: 4220: 4219: 4210: 4209: 4197: 4196: 4180: 4178: 4177: 4172: 4158: 4157: 4148: 4147: 4135: 4134: 4111: 4109: 4108: 4103: 4083: 4082: 4066: 4064: 4063: 4058: 4035: 4034: 4011: 4009: 4008: 4003: 3998: 3997: 3985: 3984: 3975: 3974: 3962: 3961: 3945: 3943: 3942: 3937: 3926: 3925: 3916: 3915: 3903: 3902: 3886: 3884: 3883: 3878: 3873: 3872: 3860: 3859: 3847: 3846: 3814:Pascal's theorem 3798:) which gives a 3766: 3764: 3763: 3758: 3732: 3730: 3729: 3724: 3716: 3715: 3703: 3702: 3686: 3684: 3683: 3678: 3660: 3658: 3657: 3652: 3636: 3634: 3633: 3628: 3609: 3589: 3587: 3586: 3581: 3558: 3556: 3555: 3550: 3525: 3523: 3522: 3517: 3501: 3478: 3476: 3475: 3470: 3444: 3442: 3441: 3436: 3404: 3402: 3401: 3396: 3394: 3389: 3380: 3378: 3377: 3372: 3349: 3347: 3346: 3341: 3313: 3311: 3310: 3305: 3289: 3266: 3264: 3263: 3258: 3235: 3233: 3232: 3227: 3203: 3201: 3200: 3195: 3184: 3183: 3156: 3155: 3124: 3122: 3121: 3116: 3074:linear system, ( 3070: 3069: 3058: 3057: 3050: 3048: 3047: 3042: 3039: 3032: 3031: 3030: 3024: 3009: 2983: 2981: 2980: 2975: 2957: 2955: 2954: 2949: 2944: 2942: 2934: 2929: 2927: 2912: 2910: 2909: 2904: 2886: 2884: 2883: 2878: 2857: 2855: 2854: 2849: 2828: 2826: 2825: 2820: 2799: 2797: 2796: 2791: 2773: 2771: 2770: 2765: 2757: 2756: 2741: 2740: 2708:compactification 2669: 2667: 2666: 2661: 2641: 2639: 2638: 2633: 2621: 2619: 2618: 2613: 2601: 2599: 2598: 2593: 2557: 2555: 2554: 2549: 2525: 2523: 2522: 2517: 2494: 2493: 2481: 2480: 2464: 2462: 2461: 2456: 2433: 2432: 2420: 2419: 2403: 2401: 2400: 2395: 2372: 2371: 2359: 2358: 2342: 2340: 2339: 2334: 2310: 2308: 2307: 2302: 2274: 2272: 2271: 2266: 2261: 2260: 2179: 2177: 2176: 2171: 2166: 2165: 2120: 2119: 2089: 2088: 2066: 2064: 2063: 2058: 2021: 2019: 2018: 2013: 1986: 1984: 1983: 1978: 1973: 1972: 1921: 1919: 1918: 1913: 1881: 1880: 1850: 1849: 1822: 1820: 1819: 1814: 1742: 1740: 1739: 1734: 1717: 1715: 1714: 1709: 1683: 1682: 1655: 1654: 1623: 1621: 1620: 1615: 1552: 1550: 1549: 1544: 1509: 1508: 1484: 1483: 1435: 1433: 1432: 1427: 1374: 1373: 1355: 1353: 1352: 1347: 1294: 1293: 1281: 1280: 1258: 1256: 1255: 1250: 1242: 1241: 1223: 1221: 1220: 1215: 1162: 1161: 1143: 1141: 1140: 1135: 1088: 1087: 1075: 1074: 1038: 1036: 1035: 1030: 1012: 1010: 1009: 1004: 987:degenerates for 986: 984: 983: 978: 952: 951: 939: 938: 913: 911: 910: 905: 875: 873: 872: 867: 837: 835: 834: 829: 812: 811: 793: 792: 771:, of the conic. 770: 768: 767: 762: 730: 728: 727: 722: 677: 675: 674: 669: 667: 666: 654: 653: 637: 635: 634: 629: 621: 620: 608: 607: 588: 586: 585: 580: 550: 548: 547: 542: 525: 524: 512: 511: 481: 479: 478: 473: 443: 441: 440: 435: 390: 388: 387: 382: 374: 373: 361: 360: 328: 324: 320: 309: 302: 283:line at infinity 237:degenerate conic 224: 222: 221: 216: 208: 207: 195: 194: 177: 168: 166: 165: 160: 152: 151: 134: 123: 121: 120: 115: 101: 100: 83: 74: 72: 71: 66: 58: 57: 45: 44: 27: 4930: 4929: 4925: 4924: 4923: 4921: 4920: 4919: 4905: 4904: 4903: 4899:(30th ed.) 4891: 4886: 4868: 4782:10.1.1.111.5574 4757: 4755: 4744:Coffman, Adam, 4739: 4738: 4729: 4725: 4716: 4712: 4703: 4699: 4694: 4689: 4688: 4655: 4652: 4651: 4625: 4621: 4619: 4616: 4615: 4592: 4588: 4586: 4583: 4582: 4552: 4548: 4524: 4520: 4515: 4512: 4511: 4509: 4505: 4500: 4462: 4406: 4402: 4393: 4389: 4387: 4384: 4383: 4350: 4346: 4334: 4330: 4328: 4325: 4324: 4292: 4288: 4276: 4272: 4270: 4267: 4266: 4228: 4224: 4215: 4211: 4205: 4201: 4192: 4188: 4186: 4183: 4182: 4153: 4149: 4143: 4139: 4130: 4126: 4124: 4121: 4120: 4078: 4074: 4072: 4069: 4068: 4030: 4026: 4024: 4021: 4020: 3993: 3989: 3980: 3976: 3970: 3966: 3957: 3953: 3951: 3948: 3947: 3921: 3917: 3911: 3907: 3898: 3894: 3892: 3889: 3888: 3868: 3864: 3855: 3851: 3842: 3838: 3836: 3833: 3832: 3822: 3804:resolvent cubic 3743: 3740: 3739: 3711: 3707: 3698: 3694: 3692: 3689: 3688: 3666: 3663: 3662: 3646: 3643: 3642: 3595: 3592: 3591: 3566: 3563: 3562: 3532: 3529: 3528: 3484: 3481: 3480: 3452: 3449: 3448: 3412: 3409: 3408: 3388: 3386: 3383: 3382: 3357: 3354: 3353: 3320: 3317: 3316: 3272: 3269: 3268: 3243: 3240: 3239: 3212: 3209: 3208: 3179: 3175: 3151: 3147: 3130: 3127: 3126: 3089: 3086: 3085: 3067: 3061:External videos 3026: 3014: 3005: 3004: 3003: 3002: 2999: 2996: 2995: 2963: 2960: 2959: 2938: 2930: 2928: 2923: 2918: 2915: 2914: 2892: 2889: 2888: 2863: 2860: 2859: 2834: 2831: 2830: 2805: 2802: 2801: 2779: 2776: 2775: 2752: 2748: 2736: 2732: 2730: 2727: 2726: 2700: 2676: 2655: 2652: 2651: 2627: 2624: 2623: 2607: 2604: 2603: 2566: 2563: 2562: 2534: 2531: 2530: 2489: 2485: 2476: 2472: 2470: 2467: 2466: 2428: 2424: 2415: 2411: 2409: 2406: 2405: 2367: 2363: 2354: 2350: 2348: 2345: 2344: 2319: 2316: 2315: 2287: 2284: 2283: 2255: 2254: 2249: 2244: 2238: 2237: 2232: 2227: 2221: 2220: 2215: 2210: 2200: 2199: 2191: 2188: 2187: 2161: 2157: 2115: 2111: 2084: 2080: 2075: 2072: 2071: 2034: 2031: 2030: 1995: 1992: 1991: 1967: 1966: 1961: 1955: 1954: 1949: 1939: 1938: 1930: 1927: 1926: 1876: 1872: 1845: 1841: 1836: 1833: 1832: 1748: 1745: 1744: 1722: 1719: 1718: 1678: 1674: 1650: 1646: 1641: 1638: 1637: 1558: 1555: 1554: 1504: 1500: 1479: 1475: 1470: 1467: 1466: 1459: 1369: 1365: 1363: 1360: 1359: 1289: 1285: 1276: 1272: 1270: 1267: 1266: 1237: 1233: 1231: 1228: 1227: 1157: 1153: 1151: 1148: 1147: 1083: 1079: 1070: 1066: 1064: 1061: 1060: 1045: 1018: 1015: 1014: 992: 989: 988: 947: 943: 934: 930: 922: 919: 918: 881: 878: 877: 843: 840: 839: 807: 803: 788: 784: 779: 776: 775: 744: 741: 740: 733:complex numbers 683: 680: 679: 662: 658: 649: 645: 643: 640: 639: 616: 612: 603: 599: 597: 594: 593: 556: 553: 552: 520: 516: 507: 503: 495: 492: 491: 449: 446: 445: 396: 393: 392: 369: 365: 356: 352: 350: 347: 346: 335: 326: 322: 311: 304: 297: 257:complex numbers 247:, defined by a 229: 228: 227: 226: 225: 203: 199: 190: 186: 184: 181: 180: 178: 170: 169: 147: 143: 141: 138: 137: 135: 126: 125: 124: 96: 92: 90: 87: 86: 84: 76: 75: 53: 49: 40: 36: 34: 31: 30: 28: 17: 12: 11: 5: 4928: 4918: 4917: 4915:Conic sections 4902: 4901: 4889: 4884: 4871: 4866: 4849: 4829: 4820: 4794: 4762: 4740: 4737: 4736: 4723: 4710: 4696: 4695: 4693: 4690: 4687: 4686: 4674: 4671: 4668: 4665: 4662: 4659: 4639: 4636: 4633: 4628: 4624: 4603: 4600: 4595: 4591: 4577:which are the 4566: 4563: 4560: 4555: 4551: 4547: 4544: 4541: 4538: 4535: 4532: 4527: 4523: 4519: 4502: 4501: 4499: 4496: 4461: 4458: 4457: 4456: 4436: 4433: 4417: 4414: 4409: 4405: 4401: 4396: 4392: 4380: 4364: 4361: 4358: 4353: 4349: 4345: 4342: 4337: 4333: 4312: 4309: 4306: 4303: 4300: 4295: 4291: 4287: 4284: 4279: 4275: 4259: 4258: 4242: 4239: 4236: 4231: 4227: 4223: 4218: 4214: 4208: 4204: 4200: 4195: 4191: 4170: 4167: 4164: 4161: 4156: 4152: 4146: 4142: 4138: 4133: 4129: 4117: 4101: 4098: 4095: 4092: 4089: 4086: 4081: 4077: 4056: 4053: 4050: 4047: 4044: 4041: 4038: 4033: 4029: 4017: 4001: 3996: 3992: 3988: 3983: 3979: 3973: 3969: 3965: 3960: 3956: 3935: 3932: 3929: 3924: 3920: 3914: 3910: 3906: 3901: 3897: 3876: 3871: 3867: 3863: 3858: 3854: 3850: 3845: 3841: 3821: 3818: 3773: 3772: 3756: 3753: 3750: 3747: 3735: 3734: 3722: 3719: 3714: 3710: 3706: 3701: 3697: 3676: 3673: 3670: 3650: 3638: 3637: 3626: 3623: 3620: 3617: 3614: 3608: 3605: 3602: 3599: 3579: 3576: 3573: 3570: 3560: 3548: 3545: 3542: 3539: 3536: 3526: 3515: 3512: 3509: 3506: 3500: 3497: 3494: 3491: 3488: 3468: 3465: 3462: 3459: 3456: 3446: 3434: 3431: 3428: 3425: 3422: 3419: 3416: 3406: 3392: 3370: 3367: 3364: 3361: 3351: 3339: 3336: 3333: 3330: 3327: 3324: 3314: 3303: 3300: 3297: 3294: 3288: 3285: 3282: 3279: 3276: 3256: 3253: 3250: 3247: 3237: 3225: 3222: 3219: 3216: 3193: 3190: 3187: 3182: 3178: 3174: 3171: 3168: 3165: 3162: 3159: 3154: 3150: 3146: 3143: 3140: 3137: 3134: 3114: 3111: 3108: 3105: 3102: 3099: 3096: 3093: 3080: 3079: 3063: 3062: 3038: 3035: 3029: 3023: 3020: 3017: 3013: 3008: 2973: 2970: 2967: 2947: 2941: 2937: 2933: 2926: 2922: 2902: 2899: 2896: 2876: 2873: 2870: 2867: 2847: 2844: 2841: 2838: 2818: 2815: 2812: 2809: 2789: 2786: 2783: 2763: 2760: 2755: 2751: 2747: 2744: 2739: 2735: 2699: 2696: 2675: 2672: 2659: 2648: 2647: 2631: 2611: 2591: 2588: 2585: 2582: 2579: 2576: 2573: 2570: 2559: 2547: 2544: 2541: 2538: 2527: 2515: 2512: 2509: 2506: 2503: 2500: 2497: 2492: 2488: 2484: 2479: 2475: 2454: 2451: 2448: 2445: 2442: 2439: 2436: 2431: 2427: 2423: 2418: 2414: 2393: 2390: 2387: 2384: 2381: 2378: 2375: 2370: 2366: 2362: 2357: 2353: 2332: 2329: 2326: 2323: 2312: 2300: 2297: 2294: 2291: 2276: 2275: 2264: 2259: 2253: 2250: 2248: 2245: 2243: 2240: 2239: 2236: 2233: 2231: 2228: 2226: 2223: 2222: 2219: 2216: 2214: 2211: 2209: 2206: 2205: 2203: 2198: 2195: 2181: 2180: 2169: 2164: 2160: 2156: 2153: 2150: 2147: 2144: 2141: 2138: 2135: 2132: 2129: 2126: 2123: 2118: 2114: 2110: 2107: 2104: 2101: 2098: 2095: 2092: 2087: 2083: 2079: 2056: 2053: 2050: 2047: 2044: 2041: 2038: 2011: 2008: 2005: 2002: 1999: 1988: 1987: 1976: 1971: 1965: 1962: 1960: 1957: 1956: 1953: 1950: 1948: 1945: 1944: 1942: 1937: 1934: 1911: 1908: 1905: 1902: 1899: 1896: 1893: 1890: 1887: 1884: 1879: 1875: 1871: 1868: 1865: 1862: 1859: 1856: 1853: 1848: 1844: 1840: 1812: 1809: 1806: 1803: 1800: 1797: 1794: 1791: 1788: 1785: 1782: 1779: 1776: 1773: 1770: 1767: 1764: 1761: 1758: 1755: 1752: 1732: 1729: 1726: 1707: 1704: 1701: 1698: 1695: 1692: 1689: 1686: 1681: 1677: 1673: 1670: 1667: 1664: 1661: 1658: 1653: 1649: 1645: 1613: 1610: 1607: 1604: 1601: 1598: 1595: 1592: 1589: 1586: 1583: 1580: 1577: 1574: 1571: 1568: 1565: 1562: 1542: 1539: 1536: 1533: 1530: 1527: 1524: 1521: 1518: 1515: 1512: 1507: 1503: 1499: 1496: 1493: 1490: 1487: 1482: 1478: 1474: 1458: 1455: 1447: 1446: 1439: 1436: 1425: 1422: 1419: 1416: 1413: 1410: 1407: 1404: 1401: 1398: 1395: 1392: 1389: 1386: 1383: 1380: 1377: 1372: 1368: 1356: 1345: 1342: 1339: 1336: 1333: 1330: 1327: 1324: 1321: 1318: 1315: 1312: 1309: 1306: 1303: 1300: 1297: 1292: 1288: 1284: 1279: 1275: 1259: 1248: 1245: 1240: 1236: 1224: 1213: 1210: 1207: 1204: 1201: 1198: 1195: 1192: 1189: 1186: 1183: 1180: 1177: 1174: 1171: 1168: 1165: 1160: 1156: 1144: 1133: 1130: 1127: 1124: 1121: 1118: 1115: 1112: 1109: 1106: 1103: 1100: 1097: 1094: 1091: 1086: 1082: 1078: 1073: 1069: 1044: 1043:Classification 1041: 1028: 1025: 1022: 1002: 999: 996: 976: 973: 970: 967: 964: 961: 958: 955: 950: 946: 942: 937: 933: 929: 926: 903: 900: 897: 894: 891: 888: 885: 865: 862: 859: 856: 853: 850: 847: 827: 824: 821: 818: 815: 810: 806: 802: 799: 796: 791: 787: 783: 760: 757: 754: 751: 748: 720: 717: 714: 711: 708: 705: 702: 699: 696: 693: 690: 687: 665: 661: 657: 652: 648: 627: 624: 619: 615: 611: 606: 602: 578: 575: 572: 569: 566: 563: 560: 540: 537: 534: 531: 528: 523: 519: 515: 510: 506: 502: 499: 471: 468: 465: 462: 459: 456: 453: 433: 430: 427: 424: 421: 418: 415: 412: 409: 406: 403: 400: 380: 377: 372: 368: 364: 359: 355: 334: 331: 214: 211: 206: 202: 198: 193: 189: 179: 172: 171: 158: 155: 150: 146: 136: 129: 128: 127: 113: 110: 107: 104: 99: 95: 85: 78: 77: 64: 61: 56: 52: 48: 43: 39: 29: 22: 21: 20: 19: 18: 15: 9: 6: 4: 3: 2: 4927: 4916: 4913: 4912: 4910: 4898: 4894: 4890: 4887: 4885:0-486-45773-7 4881: 4877: 4872: 4869: 4863: 4858: 4857: 4850: 4847: 4843: 4839: 4835: 4830: 4826: 4821: 4818: 4814: 4810: 4806: 4802: 4801: 4795: 4792: 4788: 4783: 4778: 4774: 4770: 4769: 4763: 4754:on 2018-07-02 4753: 4749: 4748: 4742: 4741: 4733: 4727: 4720: 4714: 4707: 4701: 4697: 4672: 4666: 4663: 4660: 4657: 4637: 4634: 4631: 4626: 4622: 4601: 4598: 4593: 4589: 4580: 4564: 4561: 4558: 4553: 4549: 4542: 4539: 4536: 4530: 4525: 4521: 4517: 4507: 4503: 4495: 4492: 4490: 4485: 4483: 4482:parallelogram 4479: 4473: 4471: 4467: 4454: 4450: 4446: 4442: 4437: 4434: 4431: 4415: 4412: 4407: 4403: 4399: 4394: 4390: 4381: 4378: 4362: 4359: 4356: 4351: 4347: 4343: 4340: 4335: 4331: 4310: 4307: 4304: 4301: 4298: 4293: 4289: 4285: 4282: 4277: 4273: 4264: 4263: 4262: 4256: 4240: 4237: 4234: 4229: 4225: 4221: 4216: 4212: 4206: 4202: 4198: 4193: 4189: 4168: 4165: 4162: 4159: 4154: 4150: 4144: 4140: 4136: 4131: 4127: 4118: 4115: 4099: 4096: 4093: 4090: 4087: 4084: 4079: 4075: 4054: 4051: 4048: 4045: 4042: 4039: 4036: 4031: 4027: 4018: 4015: 3999: 3994: 3990: 3986: 3981: 3977: 3971: 3967: 3963: 3958: 3954: 3933: 3930: 3927: 3922: 3918: 3912: 3908: 3904: 3899: 3895: 3874: 3869: 3865: 3861: 3856: 3852: 3848: 3843: 3839: 3830: 3829: 3828: 3825: 3817: 3815: 3811: 3807: 3805: 3801: 3797: 3796:Faucette 1996 3792: 3790: 3786: 3782: 3778: 3770: 3754: 3751: 3748: 3745: 3737: 3736: 3720: 3717: 3712: 3708: 3704: 3699: 3695: 3668: 3648: 3641:(dividing by 3640: 3639: 3624: 3621: 3618: 3615: 3612: 3606: 3603: 3600: 3597: 3577: 3571: 3568: 3561: 3546: 3543: 3540: 3537: 3534: 3527: 3513: 3510: 3507: 3504: 3498: 3495: 3492: 3489: 3486: 3466: 3463: 3460: 3457: 3454: 3447: 3432: 3429: 3426: 3423: 3420: 3417: 3414: 3407: 3390: 3368: 3365: 3362: 3359: 3352: 3337: 3334: 3331: 3328: 3325: 3322: 3315: 3301: 3298: 3295: 3292: 3286: 3283: 3280: 3277: 3274: 3254: 3251: 3248: 3245: 3238: 3223: 3220: 3217: 3214: 3207: 3206: 3205: 3191: 3188: 3185: 3180: 3176: 3169: 3166: 3163: 3157: 3152: 3148: 3141: 3138: 3135: 3112: 3106: 3103: 3100: 3097: 3094: 3077: 3073: 3064: 3059: 3056: 3054: 3036: 3033: 3021: 3018: 3015: 3011: 2993: 2989: 2984: 2971: 2968: 2965: 2945: 2935: 2924: 2920: 2900: 2897: 2894: 2874: 2871: 2868: 2865: 2845: 2842: 2839: 2836: 2816: 2813: 2810: 2807: 2787: 2784: 2781: 2761: 2758: 2753: 2749: 2745: 2742: 2737: 2733: 2725:) defined by 2724: 2720: 2715: 2713: 2709: 2705: 2695: 2694:for details. 2693: 2689: 2685: 2681: 2671: 2657: 2645: 2629: 2609: 2589: 2586: 2583: 2580: 2577: 2574: 2571: 2568: 2560: 2545: 2542: 2539: 2528: 2513: 2507: 2504: 2501: 2495: 2490: 2486: 2482: 2477: 2473: 2452: 2446: 2443: 2440: 2434: 2429: 2425: 2421: 2416: 2412: 2391: 2385: 2382: 2379: 2373: 2368: 2364: 2360: 2355: 2351: 2330: 2327: 2324: 2313: 2298: 2295: 2292: 2281: 2280: 2279: 2262: 2257: 2251: 2246: 2241: 2234: 2229: 2224: 2217: 2212: 2207: 2201: 2196: 2193: 2186: 2185: 2184: 2167: 2162: 2158: 2154: 2151: 2148: 2145: 2142: 2139: 2136: 2133: 2130: 2127: 2124: 2121: 2116: 2112: 2108: 2105: 2102: 2099: 2096: 2093: 2090: 2085: 2081: 2077: 2070: 2069: 2068: 2051: 2048: 2045: 2042: 2039: 2028: 2023: 2006: 2003: 2000: 1974: 1969: 1963: 1958: 1951: 1946: 1940: 1935: 1932: 1925: 1924: 1923: 1909: 1906: 1903: 1900: 1897: 1894: 1891: 1888: 1885: 1882: 1877: 1873: 1869: 1866: 1863: 1860: 1857: 1854: 1851: 1846: 1842: 1838: 1830: 1810: 1807: 1804: 1798: 1795: 1792: 1789: 1786: 1783: 1780: 1771: 1768: 1765: 1762: 1759: 1756: 1753: 1730: 1727: 1724: 1705: 1702: 1699: 1696: 1693: 1690: 1687: 1684: 1679: 1675: 1671: 1668: 1665: 1662: 1659: 1656: 1651: 1647: 1643: 1634: 1627: 1611: 1608: 1605: 1599: 1596: 1593: 1590: 1587: 1584: 1575: 1572: 1569: 1566: 1563: 1540: 1537: 1534: 1531: 1528: 1525: 1522: 1519: 1516: 1513: 1510: 1505: 1501: 1497: 1494: 1491: 1488: 1485: 1480: 1476: 1472: 1463: 1454: 1452: 1444: 1440: 1437: 1423: 1420: 1414: 1411: 1408: 1399: 1396: 1393: 1384: 1381: 1378: 1375: 1370: 1366: 1357: 1343: 1340: 1334: 1331: 1328: 1325: 1316: 1313: 1310: 1307: 1298: 1295: 1290: 1286: 1282: 1277: 1273: 1264: 1260: 1246: 1243: 1238: 1234: 1225: 1211: 1208: 1202: 1199: 1196: 1187: 1184: 1181: 1172: 1169: 1166: 1163: 1158: 1154: 1145: 1131: 1128: 1122: 1119: 1116: 1107: 1104: 1101: 1092: 1089: 1084: 1080: 1076: 1071: 1067: 1058: 1057: 1056: 1053: 1051: 1040: 1026: 1023: 1020: 1000: 997: 994: 974: 971: 968: 965: 962: 956: 953: 948: 944: 940: 935: 931: 924: 915: 901: 898: 895: 892: 889: 886: 883: 863: 860: 857: 854: 851: 848: 845: 825: 822: 816: 813: 808: 804: 797: 794: 789: 785: 781: 772: 755: 752: 749: 738: 734: 715: 712: 709: 706: 697: 694: 691: 688: 663: 659: 655: 650: 646: 625: 622: 617: 613: 609: 604: 600: 590: 576: 573: 570: 567: 564: 561: 558: 538: 535: 532: 529: 521: 517: 513: 508: 504: 497: 490:of equations 489: 485: 469: 466: 463: 460: 457: 454: 451: 431: 428: 422: 419: 416: 407: 404: 401: 378: 375: 370: 366: 362: 357: 353: 339: 330: 318: 314: 307: 300: 295: 290: 288: 284: 279: 277: 274:and a double 273: 269: 264: 262: 258: 254: 250: 246: 242: 238: 234: 212: 209: 204: 200: 196: 191: 187: 176: 156: 153: 148: 144: 133: 111: 108: 105: 102: 97: 93: 82: 62: 59: 54: 50: 46: 41: 37: 26: 4896: 4875: 4855: 4837: 4833: 4824: 4804: 4798: 4775:(1): 51–57, 4772: 4766: 4756:, retrieved 4752:the original 4746: 4726: 4713: 4700: 4506: 4493: 4486: 4474: 4463: 4451:, this is a 4441:line segment 4429: 4376: 4260: 4254: 4113: 4013: 3826: 3823: 3820:Degeneration 3808: 3793: 3784: 3780: 3776: 3774: 3768: 3083: 2985: 2716: 2701: 2698:Applications 2677: 2649: 2277: 2182: 2026: 2024: 1989: 1829:discriminant 1826: 1457:Discriminant 1448: 1443:affine plane 1054: 1046: 916: 773: 591: 344: 316: 312: 305: 298: 291: 280: 265: 236: 230: 4811:: 362–364, 2027:homogeneous 245:plane curve 4758:2013-07-03 4719:Spain 2007 4692:References 4379:goes to 0. 4016:goes to 0. 3769:projective 488:hyperbolas 4878:, Dover, 4860:, Dover, 4777:CiteSeerX 4670:∞ 4540:− 4478:trapezoid 4400:− 4341:− 4299:− 4283:− 4222:− 4160:− 4085:− 4046:− 4037:− 3964:− 3905:− 3849:− 3789:Levy 1964 3779:reverses 3705:− 3675:∞ 3672:→ 3619:− 3575:∞ 3541:− 3493:− 3461:− 3415:− 3281:− 3167:− 3104:± 3095:± 2785:≠ 1796:− 1769:− 1694:− 1685:− 1597:− 1567:− 1529:− 1511:− 1498:− 1486:− 1412:− 1388:⇔ 1329:− 1302:⇔ 1200:− 1176:⇔ 1164:− 1120:− 1096:⇔ 1077:− 963:− 954:− 814:− 731:over the 710:− 530:− 514:− 405:− 363:− 103:− 47:− 4909:Category 333:Examples 233:geometry 4846:3602237 4817:2309606 4791:2975214 3687:yields 3076:Coffman 2682:with a 2644:circles 1624:is the 482:in the 294:pencils 4882:  4864:  4844:  4815:  4789:  4779:  3610:  3502:  3290:  3072:Type I 2719:pencil 484:pencil 4842:JSTOR 4813:JSTOR 4807:(5), 4787:JSTOR 4498:Notes 4449:orbit 3771:line. 2680:plane 1626:union 272:plane 270:of a 241:conic 239:is a 4880:ISBN 4862:ISBN 4614:and 4445:foci 3783:and 3749:> 3538:< 3427:< 3421:< 3332:< 3326:< 3218:> 2898:< 2840:> 2688:apex 2684:cone 2622:and 2602:and 2543:> 2496:< 2374:> 2296:< 325:and 303:and 276:cone 235:, a 4773:103 4428:as 4253:as 4112:as 4012:as 3055:). 2710:of 2537:det 2322:det 2290:det 486:of 319:= 0 308:= 0 301:= 0 231:In 4911:: 4895:, 4838:13 4836:, 4805:64 4803:, 4785:, 4771:, 4491:. 3806:. 3405:); 3078:). 2972:0. 2714:. 1799:12 1706:72 1697:36 1688:54 1660:12 1523:10 1039:. 539:0. 317:bg 315:+ 313:af 4734:) 4730:( 4721:) 4717:( 4708:) 4704:( 4673:. 4667:, 4664:1 4661:, 4658:0 4638:, 4635:1 4632:= 4627:2 4623:y 4602:1 4599:= 4594:2 4590:x 4565:, 4562:1 4559:= 4554:2 4550:y 4546:) 4543:a 4537:1 4534:( 4531:+ 4526:2 4522:x 4518:a 4455:. 4430:a 4416:0 4413:= 4408:2 4404:a 4395:2 4391:x 4377:a 4363:, 4360:0 4357:= 4352:2 4348:y 4344:a 4336:2 4332:x 4311:, 4308:0 4305:= 4302:1 4294:2 4290:y 4286:a 4278:2 4274:x 4255:a 4241:, 4238:0 4235:= 4230:2 4226:a 4217:2 4213:y 4207:2 4203:a 4199:+ 4194:2 4190:x 4169:0 4166:= 4163:1 4155:2 4151:y 4145:2 4141:a 4137:+ 4132:2 4128:x 4114:a 4100:, 4097:0 4094:= 4091:y 4088:a 4080:2 4076:x 4055:0 4052:= 4049:1 4043:y 4040:a 4032:2 4028:x 4014:a 4000:, 3995:2 3991:a 3987:= 3982:2 3978:y 3972:2 3968:a 3959:2 3955:x 3934:, 3931:1 3928:= 3923:2 3919:y 3913:2 3909:a 3900:2 3896:x 3875:, 3870:2 3866:a 3862:= 3857:2 3853:y 3844:2 3840:x 3785:y 3781:x 3777:a 3755:, 3752:1 3746:a 3733:) 3721:0 3718:= 3713:2 3709:y 3700:2 3696:x 3669:a 3649:a 3625:; 3622:x 3616:= 3613:y 3607:, 3604:x 3601:= 3598:y 3578:: 3572:= 3569:a 3547:: 3544:1 3535:a 3514:; 3511:1 3508:= 3505:y 3499:, 3496:1 3490:= 3487:y 3467:: 3464:1 3458:= 3455:a 3433:: 3430:0 3424:a 3418:1 3391:2 3369:: 3366:0 3363:= 3360:a 3338:: 3335:1 3329:a 3323:0 3302:; 3299:1 3296:= 3293:x 3287:, 3284:1 3278:= 3275:x 3255:: 3252:1 3249:= 3246:a 3224:: 3221:1 3215:a 3192:, 3189:2 3186:= 3181:2 3177:y 3173:) 3170:a 3164:1 3161:( 3158:+ 3153:2 3149:x 3145:) 3142:a 3139:+ 3136:1 3133:( 3113:, 3110:) 3107:1 3101:, 3098:1 3092:( 3037:3 3034:= 3028:) 3022:2 3019:, 3016:2 3012:4 3007:( 2969:= 2966:a 2946:, 2940:| 2936:a 2932:| 2925:/ 2921:1 2901:0 2895:a 2875:, 2872:0 2869:= 2866:a 2846:, 2843:0 2837:a 2817:; 2814:0 2811:= 2808:a 2788:0 2782:a 2762:1 2759:= 2754:2 2750:y 2746:a 2743:+ 2738:2 2734:x 2658:Q 2630:E 2610:D 2590:, 2587:0 2584:= 2581:C 2578:= 2575:B 2572:= 2569:A 2558:. 2546:0 2540:M 2526:. 2514:F 2511:) 2508:C 2505:+ 2502:A 2499:( 2491:2 2487:E 2483:+ 2478:2 2474:D 2453:F 2450:) 2447:C 2444:+ 2441:A 2438:( 2435:= 2430:2 2426:E 2422:+ 2417:2 2413:D 2392:F 2389:) 2386:C 2383:+ 2380:A 2377:( 2369:2 2365:E 2361:+ 2356:2 2352:D 2331:0 2328:= 2325:M 2299:0 2293:M 2263:. 2258:] 2252:F 2247:E 2242:D 2235:E 2230:C 2225:B 2218:D 2213:B 2208:A 2202:[ 2197:= 2194:Q 2168:; 2163:2 2159:z 2155:F 2152:+ 2149:z 2146:y 2143:E 2140:2 2137:+ 2134:z 2131:x 2128:D 2125:2 2122:+ 2117:2 2113:y 2109:C 2106:+ 2103:y 2100:x 2097:B 2094:2 2091:+ 2086:2 2082:x 2078:A 2055:) 2052:z 2049:, 2046:y 2043:, 2040:x 2037:( 2010:) 2007:y 2004:, 2001:x 1998:( 1975:, 1970:] 1964:C 1959:B 1952:B 1947:A 1941:[ 1936:= 1933:M 1910:F 1907:+ 1904:y 1901:E 1898:2 1895:+ 1892:x 1889:D 1886:2 1883:+ 1878:2 1874:y 1870:C 1867:+ 1864:y 1861:x 1858:B 1855:2 1852:+ 1847:2 1843:x 1839:A 1811:, 1808:0 1805:= 1802:) 1793:y 1790:2 1787:+ 1784:x 1781:3 1778:( 1775:) 1772:6 1766:y 1763:2 1760:+ 1757:x 1754:3 1751:( 1731:, 1728:0 1725:= 1703:+ 1700:y 1691:x 1680:2 1676:y 1672:4 1669:+ 1666:y 1663:x 1657:+ 1652:2 1648:x 1644:9 1612:, 1609:0 1606:= 1603:) 1600:9 1594:y 1591:+ 1588:x 1585:3 1582:( 1579:) 1576:1 1573:+ 1570:y 1564:x 1561:( 1541:, 1538:0 1535:= 1532:9 1526:y 1520:+ 1517:x 1514:6 1506:2 1502:y 1495:y 1492:x 1489:2 1481:2 1477:x 1473:3 1445:) 1424:0 1421:= 1418:) 1415:i 1409:x 1406:( 1403:) 1400:i 1397:+ 1394:x 1391:( 1385:0 1382:= 1379:1 1376:+ 1371:2 1367:x 1344:0 1341:= 1338:) 1335:y 1332:i 1326:x 1323:( 1320:) 1317:y 1314:i 1311:+ 1308:x 1305:( 1299:0 1296:= 1291:2 1287:y 1283:+ 1278:2 1274:x 1247:0 1244:= 1239:2 1235:x 1212:0 1209:= 1206:) 1203:1 1197:x 1194:( 1191:) 1188:1 1185:+ 1182:x 1179:( 1173:0 1170:= 1167:1 1159:2 1155:x 1132:0 1129:= 1126:) 1123:y 1117:x 1114:( 1111:) 1108:y 1105:+ 1102:x 1099:( 1093:0 1090:= 1085:2 1081:y 1072:2 1068:x 1027:0 1024:= 1021:x 1001:0 998:= 995:a 975:0 972:= 969:x 966:b 960:) 957:1 949:2 945:y 941:+ 936:2 932:x 928:( 925:a 902:0 899:= 896:b 893:, 890:1 887:= 884:a 864:1 861:= 858:b 855:, 852:0 849:= 846:a 826:0 823:= 820:) 817:1 809:2 805:y 801:( 798:b 795:+ 790:2 786:x 782:a 759:) 756:0 753:, 750:0 747:( 719:) 716:y 713:i 707:x 704:( 701:) 698:y 695:i 692:+ 689:x 686:( 664:2 660:y 656:+ 651:2 647:x 626:0 623:= 618:2 614:y 610:+ 605:2 601:x 577:1 574:= 571:b 568:, 565:0 562:= 559:a 536:= 533:b 527:) 522:2 518:y 509:2 505:x 501:( 498:a 470:0 467:= 464:b 461:, 458:1 455:= 452:a 432:0 429:= 426:) 423:y 420:+ 417:x 414:( 411:) 408:y 402:x 399:( 379:0 376:= 371:2 367:y 358:2 354:x 327:g 323:f 306:g 299:f 213:0 210:= 205:2 201:y 197:+ 192:2 188:x 157:0 154:= 149:2 145:x 112:0 109:= 106:1 98:2 94:x 63:0 60:= 55:2 51:y 42:2 38:x

Index

coordinate plane with x-shaped cross through the origin
coordinate plane with two parallel lines either side of the y-axis
coordinate plane with single line coinciding with the y-axis
coordinate plane with a single point marked at origin
geometry
conic
plane curve
polynomial equation
irreducible curve
complex numbers
algebraically closed field
three-dimensional space
plane
cone
line at infinity
complex conjugate lines
pencils

pencil
hyperbolas
complex numbers
complex conjugate lines
projective transformation
complex conjugate lines
affine plane
affine transformations

union

discriminant

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